US20060066971A1 - System and method for ameliorating the effects of adjacent track erasure in magnetic data storage device - Google Patents

System and method for ameliorating the effects of adjacent track erasure in magnetic data storage device Download PDF

Info

Publication number
US20060066971A1
US20060066971A1 US10/956,898 US95689804A US2006066971A1 US 20060066971 A1 US20060066971 A1 US 20060066971A1 US 95689804 A US95689804 A US 95689804A US 2006066971 A1 US2006066971 A1 US 2006066971A1
Authority
US
United States
Prior art keywords
track
victim
aggressor
tracks
controller
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US10/956,898
Inventor
Michael Alex
Hideki Zaitsu
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
HGST Netherlands BV
Original Assignee
Hitachi Global Storage Technologies Netherlands BV
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hitachi Global Storage Technologies Netherlands BV filed Critical Hitachi Global Storage Technologies Netherlands BV
Priority to US10/956,898 priority Critical patent/US20060066971A1/en
Assigned to HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS B.V reassignment HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS B.V ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: ZAITSU, HIDEKI, ALEX, MICHAEL
Publication of US20060066971A1 publication Critical patent/US20060066971A1/en
Abandoned legal-status Critical Current

Links

Images

Classifications

    • GPHYSICS
    • G11INFORMATION STORAGE
    • G11BINFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/012Recording on, or reproducing or erasing from, magnetic disks
    • GPHYSICS
    • G11INFORMATION STORAGE
    • G11BINFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B20/00Signal processing not specific to the method of recording or reproducing; Circuits therefor
    • G11B20/10Digital recording or reproducing
    • GPHYSICS
    • G11INFORMATION STORAGE
    • G11BINFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B2220/00Record carriers by type
    • G11B2220/20Disc-shaped record carriers
    • G11B2220/25Disc-shaped record carriers characterised in that the disc is based on a specific recording technology
    • G11B2220/2508Magnetic discs
    • G11B2220/2516Hard disks

Definitions

  • the present invention relates generally to hard disk drives.
  • ATE adjacent track erasure
  • ATI adjacent track interference
  • AATE@ side writing/side erasure
  • heads are designed such that no ATE failure occurs in the short term, or heads that are considered marginal are discarded and never used in drives. Because of this, head designs are optimized and constrained to insure good short term performance, which means that recording performance will be compromised, since reducing the effects of ATE requires design modifications that can negatively impact other recording performance metrics, like so-called overwrite (OW).
  • OW overwrite
  • marginal heads that may or may not cause ATE in the long run are discarded during testing and sorting, causing lower head yields.
  • the present invention recognizes that the effects of applied stray fields are cumulative in nature with well-known characteristics, and that a victim track that is affected by writes to another track may or may not be immediately adjacent to the written track, depending on the geometry of the head. Generally speaking, regardless of where the affected track is, the amplitude decay is logarithmic with the number of exposures to the field.
  • ATE may be caused to immediately adjacent tracks to a written track, and in perpendicular recording to tracks near the edges of the return pole, which is relatively larger than the main pole and accordingly the edges of which can be distanced from the track being written (the track under the main pole). Further, ATE can be caused to tracks near the edges of head shields, which can occur not just during writes but also if the head is placed in a global field of sufficient amplitude. Having made these critical observations, the invention herein is provided.
  • a controller for a hard disk drive (HDD) that can use longitudinal recording or perpendicular recording executes logic.
  • the logic may be to correlate an aggressor track on a disk of the HDD to at least one victim track on the disk, and then to count a number of times the aggressor track is written to. When the number of times violates a threshold, data on the victim track can be rewritten.
  • the logic may include scanning a victim track for errors, and if the errors exceed a threshold, determining that the victim track must be rewritten. In this latter embodiment, the error rate of the victim track can be scanned at predetermined intervals or after a predetermined number of writes.
  • a track can be considered to be a victim track of an aggressor track by virtue of the victim track being exposed to a magnetic field associated with a write of the aggressor track.
  • a hard disk drive determines that a rewrite condition has been met for at least a first data track due to aggressor writes of a nearby data track which potentially expose the first data track to stray magnetic flux.
  • the HDD can in response rewrite data on the first data track.
  • a chip for a hard disk drive (HDD) which has data tracks. At least one victim track is correlated to at least one aggressor track by virtue of the victim track being expected to receive exposure to stray magnetic flux when the aggressor track is written to.
  • the chip can include means for determining whether a rewrite condition has been met, and means for rewriting data stored on the victim track back to the victim track, in response to the means for determining.
  • FIG. 1 is a perspective view of an exemplary embodiment of the present magnetic storage device, configured as a hard disk drive, with portions of the housing broken away;
  • FIG. 2 is a flow chart of a first embodiment of the present logic
  • FIG. 3 is a flow chart of a second embodiment of the present logic.
  • a magnetic data storage device for storing data on a storage medium 12 that in one embodiment may be implemented by plural storage disks in a hard disk drive (HDD).
  • the device 10 When implemented as a hard disk drive, the device 10 includes an arm 14 having a read/write head 16 (part of what is colloquially referred to as a “slider”) on the end thereof in accordance with hard disk drive principles.
  • the data storage region 12 may be managed by a controller 18 that can be a conventional hard disk drive controller implemented as a chip and modified per the logic below.
  • the controller 18 controls an electromechanical actuator 20 by sending signals over a path 22 in accordance with principles known in the art to read data from and to write data to the disks 12 .
  • the write head e.g., the main pole of a perpendicular recording head, it being understood that the principles advanced herein apply to both perpendicular and longitudinal recording
  • the write head is positioned over the track N and the write is executed.
  • one or more nearby tracks N+ ⁇ might experience stray magnetic fields when the N th track is written, thereby potentially causing ATE in the track or tracks N+ ⁇ .
  • the N th track being written can be considered to be an “aggressor” track, and any adjacent tracks that are potentially affected by the writing of the N th track can be considered to be “victim tracks” associated with the aggressor track N.
  • the present invention understands that data erasure on victim tracks from stray fields caused by writes to aggressor tracks, which leads to amplitude loss (and noise increase), is not always an abrupt catastrophic process.
  • the drive may perform adequately for many data writes on track N and there may be no failure on any adjacent tracks until very many writes has taken place.
  • victim track-aggressor track correlations can be made at block 100 . This can be done in accordance with principles set forth above empirically or experimentally by characterizing the drive and its components: head, media, the physical crosstrack locations of regions that may be erased due to ATE effects, etc. In this way, for writes to each track (an Aaggressor track@ when it is being written to), it can be determined which other track or tracks (the Avictim@ tracks) can experience ATE, with each track consequently being a potential aggressor track when it is written to and a potential victim track when another track nearby is written to.
  • the logic moves to block 102 to establish a threshold number of writes to an aggressor track beyond which the associated victim tracks might be expected to experience degradation and, hence, require rewrite as set forth more fully below.
  • a single threshold can be used for all potential victim tracks, or each potential victim track can have its own threshold determined in cases where system geometry might produce ATE in some tracks with fewer aggressor writes than would produce ATE in other tracks.
  • the value of the threshold may be determined experimentally and set conservatively to ensure that as long as a rewrite is performed as discussed below, the likelihood of data loss of significance due to ATE is minimized.
  • the HDD can be provided to a user and the logic can flow to block 104 to keep track of the number of writes performed on each track, and, hence, the total number of “aggressor writes” each nearby track, in its role of victim track, has been the victim of. That is, for each potential victim track, the number of times any associated aggressor tracks are written are counted at block 104 .
  • decision diamond 106 it is determined whether any victim track count violates the threshold. If the count does not violate the threshold number, then the logic loops back to block 104 to continue to count the number of times potential aggressor tracks are written. In contrast, if the number of aggressor writes experienced by a potential victim track equals or exceeds or otherwise violates the threshold that was established at block 102 , the victim track will be examined, at decision diamond 108 , to see if any data previously has been written to the victim track. If so, then the data on this track is rewritten at block 110 , preferably back to the same track, substantially before there is any danger of data loss. If no data is written to the victim track or from decision diamond 108 if the test there was negative, the logic loops back to block 104 .
  • the range of writes that might produce ATE can be given lower and upper bounds at block 112 and the potential victim tracks determined from head geometry in accordance with principles set forth above.
  • the potential victim tracks are scanned for errors at block 114 . More generally, potential victim tracks are scanned for errors using, e.g., error rate determination principles known in the art, based on some heuristic rule.

Abstract

To ameliorate the effects of ATE in a HDD, tracks that are potential victim tracks of an aggressor track by virtue of the victim tracks being exposed to a magnetic field associated with a write of the aggressor track are preemptively rewritten after an empirically-determined number of writes to the aggressor track, with the empirically-determined number of writes being selected to ensure that the cumulative effects of aggressor writes do not rise to the level that would be expected to result in a significant amount of lost data on the victim tracks. Alternatively, potential victim tracks can be scanned for error rates and if any error rates violate a threshold, the victim tracks can be rewritten when the disk is idle.

Description

    I. FIELD OF THE INVENTION
  • The present invention relates generally to hard disk drives.
  • II. BACKGROUND OF THE INVENTION
  • In hard disk drives (HDD), deleterious effects can occur that are known as “adjacent track erasure” (ATE), “adjacent track interference” (ATI), and “side writing/side erasure” (herein collectively referred to as AATE@). These phenomena are all caused by inadvertent erasure of data that is underneath certain portions of the recording head during disk drive operation. There are presently no known solutions to this problem, other than to discard a head known to cause ATE and to design heads such that ATE effects are minimized, but due to process and material variations, a head designed to produce little or no ATE may still exhibit poor ATE performance, that is, cause inadvertent erasure of victim data tracks in the drive. Generally, ATE is not a serious issue in the short term for nominally good head designs, but repeated use of the head in the drive causes gradual performance degradation over time because data on adjacent tracks is increasingly erased as the head is used.
  • To avoid long term drive failure, heads are designed such that no ATE failure occurs in the short term, or heads that are considered marginal are discarded and never used in drives. Because of this, head designs are optimized and constrained to insure good short term performance, which means that recording performance will be compromised, since reducing the effects of ATE requires design modifications that can negatively impact other recording performance metrics, like so-called overwrite (OW). In addition, as mentioned above “marginal” heads that may or may not cause ATE in the long run are discarded during testing and sorting, causing lower head yields. The present invention recognizes that the effects of applied stray fields are cumulative in nature with well-known characteristics, and that a victim track that is affected by writes to another track may or may not be immediately adjacent to the written track, depending on the geometry of the head. Generally speaking, regardless of where the affected track is, the amplitude decay is logarithmic with the number of exposures to the field.
  • With more specificity, ATE may be caused to immediately adjacent tracks to a written track, and in perpendicular recording to tracks near the edges of the return pole, which is relatively larger than the main pole and accordingly the edges of which can be distanced from the track being written (the track under the main pole). Further, ATE can be caused to tracks near the edges of head shields, which can occur not just during writes but also if the head is placed in a global field of sufficient amplitude. Having made these critical observations, the invention herein is provided.
  • SUMMARY OF THE INVENTION
  • A controller for a hard disk drive (HDD) that can use longitudinal recording or perpendicular recording is provided that executes logic. The logic may be to correlate an aggressor track on a disk of the HDD to at least one victim track on the disk, and then to count a number of times the aggressor track is written to. When the number of times violates a threshold, data on the victim track can be rewritten. In addition or as an alternative, the logic may include scanning a victim track for errors, and if the errors exceed a threshold, determining that the victim track must be rewritten. In this latter embodiment, the error rate of the victim track can be scanned at predetermined intervals or after a predetermined number of writes. In various implementations a track can be considered to be a victim track of an aggressor track by virtue of the victim track being exposed to a magnetic field associated with a write of the aggressor track.
  • In another aspect, a hard disk drive (HDD) determines that a rewrite condition has been met for at least a first data track due to aggressor writes of a nearby data track which potentially expose the first data track to stray magnetic flux. The HDD can in response rewrite data on the first data track.
  • In still another aspect, a chip is disclosed for a hard disk drive (HDD) which has data tracks. At least one victim track is correlated to at least one aggressor track by virtue of the victim track being expected to receive exposure to stray magnetic flux when the aggressor track is written to. The chip can include means for determining whether a rewrite condition has been met, and means for rewriting data stored on the victim track back to the victim track, in response to the means for determining.
  • The details of the present invention, both as to its structure and operation, can best be understood in reference to the accompanying drawings, in which like reference numerals refer to like parts, and in which:
  • BRIEF DESCRIPTION OF THE DRAWINGS
  • FIG. 1 is a perspective view of an exemplary embodiment of the present magnetic storage device, configured as a hard disk drive, with portions of the housing broken away;
  • FIG. 2 is a flow chart of a first embodiment of the present logic; and
  • FIG. 3 is a flow chart of a second embodiment of the present logic.
  • DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
  • Referring initially to FIG. 1, a magnetic data storage device is shown, generally designated 10, for storing data on a storage medium 12 that in one embodiment may be implemented by plural storage disks in a hard disk drive (HDD). When implemented as a hard disk drive, the device 10 includes an arm 14 having a read/write head 16 (part of what is colloquially referred to as a “slider”) on the end thereof in accordance with hard disk drive principles. The data storage region 12 may be managed by a controller 18 that can be a conventional hard disk drive controller implemented as a chip and modified per the logic below. The controller 18 controls an electromechanical actuator 20 by sending signals over a path 22 in accordance with principles known in the art to read data from and to write data to the disks 12.
  • As shown in FIG. 1, when it is desired to write data to some track N, the write head (e.g., the main pole of a perpendicular recording head, it being understood that the principles advanced herein apply to both perpendicular and longitudinal recording) is positioned over the track N and the write is executed. As mentioned above, one or more nearby tracks N+δ (where δ is a positive or negative integer) might experience stray magnetic fields when the Nth track is written, thereby potentially causing ATE in the track or tracks N+δ. Under these circumstances, the Nth track being written can be considered to be an “aggressor” track, and any adjacent tracks that are potentially affected by the writing of the Nth track can be considered to be “victim tracks” associated with the aggressor track N.
  • The present invention understands that data erasure on victim tracks from stray fields caused by writes to aggressor tracks, which leads to amplitude loss (and noise increase), is not always an abrupt catastrophic process. In other words, the drive may perform adequately for many data writes on track N and there may be no failure on any adjacent tracks until very many writes has taken place.
  • With this recognition in place and referring now to FIG. 2, victim track-aggressor track correlations can be made at block 100. This can be done in accordance with principles set forth above empirically or experimentally by characterizing the drive and its components: head, media, the physical crosstrack locations of regions that may be erased due to ATE effects, etc. In this way, for writes to each track (an Aaggressor track@ when it is being written to), it can be determined which other track or tracks (the Avictim@ tracks) can experience ATE, with each track consequently being a potential aggressor track when it is written to and a potential victim track when another track nearby is written to.
  • Once the aggressor track-victim track correlations have been obtained, the logic moves to block 102 to establish a threshold number of writes to an aggressor track beyond which the associated victim tracks might be expected to experience degradation and, hence, require rewrite as set forth more fully below. A single threshold can be used for all potential victim tracks, or each potential victim track can have its own threshold determined in cases where system geometry might produce ATE in some tracks with fewer aggressor writes than would produce ATE in other tracks. The value of the threshold may be determined experimentally and set conservatively to ensure that as long as a rewrite is performed as discussed below, the likelihood of data loss of significance due to ATE is minimized.
  • After making the determinations at blocks 100 and 102, the HDD can be provided to a user and the logic can flow to block 104 to keep track of the number of writes performed on each track, and, hence, the total number of “aggressor writes” each nearby track, in its role of victim track, has been the victim of. That is, for each potential victim track, the number of times any associated aggressor tracks are written are counted at block 104.
  • At decision diamond 106 it is determined whether any victim track count violates the threshold. If the count does not violate the threshold number, then the logic loops back to block 104 to continue to count the number of times potential aggressor tracks are written. In contrast, if the number of aggressor writes experienced by a potential victim track equals or exceeds or otherwise violates the threshold that was established at block 102, the victim track will be examined, at decision diamond 108, to see if any data previously has been written to the victim track. If so, then the data on this track is rewritten at block 110, preferably back to the same track, substantially before there is any danger of data loss. If no data is written to the victim track or from decision diamond 108 if the test there was negative, the logic loops back to block 104.
  • Referring now to FIG. 3, instead of determining in detail the exact degree of correlation between aggressor tracks and victims tracks that might cause data loss on potential victim tracks, the range of writes that might produce ATE can be given lower and upper bounds at block 112 and the potential victim tracks determined from head geometry in accordance with principles set forth above. Periodically or when within the range of the total number of writes to the disk that can result in ATE to some victim track as determined at block 112, the potential victim tracks are scanned for errors at block 114. More generally, potential victim tracks are scanned for errors using, e.g., error rate determination principles known in the art, based on some heuristic rule. Regardless of what prompts the scanning, if the error rate of any track violates a threshold, the track is rewritten with the same data as it held before at block 116. As indicated in FIG. 3, this rewrite process, generally speaking, can be lengthy if it is desired to scan and rewrite the entire drive, and so it advantageously can be programmed to be done when the drive is not being used, i.e., when the drive is idle.
  • While the particular SYSTEM AND METHOD FOR AMELIORATING THE EFFECTS OF ADJACENT TRACK ERASURE IN MAGNETIC DATA STORAGE DEVICE as herein shown and described in detail is fully capable of attaining the above-described objects of the invention, it is to be understood that it is the presently preferred embodiment of the present invention and is thus representative of the subject matter which is broadly contemplated by the present invention, that the scope of the present invention fully encompasses other embodiments which may become obvious to those skilled in the art, and that the scope of the present invention is accordingly to be limited by nothing other than the appended claims, in which reference to an element in the singular is not intended to mean “one and only one” unless explicitly so stated, but rather “one or more”. Moreover, it is not necessary for a device or method to address each and every problem sought to be solved by the present invention, for it to be encompassed by the present claims. Furthermore, no element, component, or method step in the present disclosure is intended to be dedicated to the public regardless of whether the element, component, or method step is explicitly recited in the claims. No claim element herein is to be construed under the provisions of 35 U.S.C. '112, sixth paragraph, unless the element is expressly recited using the phrase “means for” or, in the case of a method claim, the element is recited as a “step” instead of an “act”. Absent express definitions herein, claim terms are to be given all ordinary and accustomed meanings that are not irreconciliable with the present specification and file history.

Claims (16)

1. A controller for a hard disk drive (HDD) and executing logic, the logic comprising:
correlating at least one aggressor track on a disk of the HDD to at least one victim track on the disk;
scanning at least one victim track for errors; and
if the errors violate a threshold, determining that the victim track must be rewritten.
2. A controller for a hard disk drive (HDD) and executing logic, the logic comprising:
correlating at least one aggressor track on a disk of the HDD to at least one victim track on the disk;
counting a number of times the aggressor track is written to; and
when the number of times violates a threshold, rewriting data on the victim track.
3. The controller of claim 2, comprising determining whether a victim track holds any data, prior to executing the rewriting act.
4. The controller of claim 2, wherein a track is a victim track of an aggressor track by virtue of the victim track being exposed to a magnetic field associated with a write of the aggressor track.
5. The controller of claim 2, wherein the logic includes:
scanning at least one victim track for errors; and
if the errors violate a threshold, determining that the victim track must be rewritten.
6. The controller of claim 5, wherein a track is a victim track of an aggressor track by virtue of the victim track being exposed to a magnetic field associated with a write of the aggressor track.
7. The controller of claim 5, wherein the victim track is scanned at predetermined intervals.
8. The controller of claim 5, wherein the victim track is scanned after a predetermined number of writes.
9. The controller of claim 1, wherein the victim track is scanned for an error rate.
10. The controller of claim 1, wherein the logic includes rewriting any victim tracks having errors violating the threshold only when the HDD is idle.
11-16. (canceled)
17. A chip for a hard disk drive (HDD) having data tracks, wherein at least one victim track is correlated to at least one aggressor track by virtue of the victim track being expected to receive exposure to stray magnetic flux when the aggressor track is written to, comprising:
means for determining whether a rewrite condition has been met; and
means for rewriting data stored on the victim track back to the victim track, responsive to the means for determining.
18. The chip of claim 17, wherein the rewrite condition is a number of writes to the aggressor track.
19. The chip of claim 17, wherein the rewrite condition is an error rate associated with the victim track.
20. The chip of claim 17, wherein the error rate is determined at predetermined intervals.
21. The chip of claim 17, wherein the error rate is determined after a predetermined number of writes.
US10/956,898 2004-09-30 2004-09-30 System and method for ameliorating the effects of adjacent track erasure in magnetic data storage device Abandoned US20060066971A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US10/956,898 US20060066971A1 (en) 2004-09-30 2004-09-30 System and method for ameliorating the effects of adjacent track erasure in magnetic data storage device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US10/956,898 US20060066971A1 (en) 2004-09-30 2004-09-30 System and method for ameliorating the effects of adjacent track erasure in magnetic data storage device

Publications (1)

Publication Number Publication Date
US20060066971A1 true US20060066971A1 (en) 2006-03-30

Family

ID=36098756

Family Applications (1)

Application Number Title Priority Date Filing Date
US10/956,898 Abandoned US20060066971A1 (en) 2004-09-30 2004-09-30 System and method for ameliorating the effects of adjacent track erasure in magnetic data storage device

Country Status (1)

Country Link
US (1) US20060066971A1 (en)

Cited By (37)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20060098318A1 (en) * 2004-11-10 2006-05-11 Feng Joseph S System and method for determining long-range erasure of adjacent tracks in hard disk drive
US20060233077A1 (en) * 2005-04-12 2006-10-19 Samsung Electronics Co., Ltd Method of protecting data on recording medium and recording medium storing program for executing the method
US20060245102A1 (en) * 2005-04-27 2006-11-02 Nelson Cheng Method and apparatus for improving the error rate of track information on a magnetic storage device
US7345837B1 (en) * 2004-12-02 2008-03-18 Maxtor Corporation Disk drive that refreshes data on portions of a disk based on a number of write operations thereto
US20080239545A1 (en) * 2007-03-28 2008-10-02 Daryl Carvis Cromer System and Method to Avoid Disk Lube Pooling
US7436610B1 (en) 2005-10-20 2008-10-14 Western Digital Technologies, Inc. Disk drive employing different zone boundaries across disk surfaces
US7518819B1 (en) 2007-08-31 2009-04-14 Western Digital Technologies, Inc. Disk drive rewriting servo sectors by writing and servoing off of temporary servo data written in data sectors
US20090237842A1 (en) * 2008-03-20 2009-09-24 Kabushiki Kaisha Toshiba 1-1 Low track-per-inch (tpi) zone with reduced need for adjacent-track-erasure (ate) refresh
US20090244775A1 (en) * 2008-03-31 2009-10-01 Kabushiki Kaisha Toshiba 1-1 Adjacent-track-erasure (ate) refresh with increased track resolution for often-written areas
US7599139B1 (en) 2007-06-22 2009-10-06 Western Digital Technologies, Inc. Disk drive having a high performance access mode and a lower performance archive mode
US7649704B1 (en) 2007-06-27 2010-01-19 Western Digital Technologies, Inc. Disk drive deferring refresh based on environmental conditions
US20100014183A1 (en) * 2008-07-17 2010-01-21 Kabushiki Kaisha Toshiba Magnetic disk drive refreshing data written to disk and data refreshment method applied to magnetic disk drive
US7672072B1 (en) 2007-06-27 2010-03-02 Western Digital Technologies, Inc. Disk drive modifying an update function for a refresh monitor in response to a measured duration
US7768729B2 (en) 2008-01-31 2010-08-03 Hitachi Global Storage Technologies Netherlands B.V. Method, system, and computer program product for estimating adjacent track erasure risk by determining erase band width growth rates
US20110026159A1 (en) * 2009-07-31 2011-02-03 Western Digital Technologies, Inc. Disk drive biasing refresh zone counters based on write commands
US20110075290A1 (en) * 2009-09-25 2011-03-31 Lenovo (Singapore) Pte. Ltd. Systems and methods for adjacent track interference (ati) risk management
US7929234B1 (en) 2009-03-27 2011-04-19 Western Digital Technologies, Inc. Disk drive prioritizing in-the-field defect scanning based on number of write operations in each of a plurality of defect zones
US7945727B2 (en) 2007-07-27 2011-05-17 Western Digital Technologies, Inc. Disk drive refreshing zones in segments to sustain target throughput of host commands
US8004785B1 (en) 2008-05-09 2011-08-23 Western Digital Technologies, Inc. Disk drive write verifying unformatted data sectors
US8014097B1 (en) 2010-05-07 2011-09-06 Hitachi Global Storage Technologies Netherlands B.V. Disk drive with adaptive counting of writes to the data tracks for minimizing the effect of adjacent track encroachment
US8023215B1 (en) 2010-05-25 2011-09-20 Seagate Technology Llc Data recovery scan based on head performance
US8094396B1 (en) 2010-02-11 2012-01-10 Western Digital Technologies, Inc. Media defect scan
US8094401B1 (en) 2008-03-17 2012-01-10 Western Digital Technologies, Inc. Writing high frequency pattern over a DC background to detect skip track erasure for a disk drive
US8174780B1 (en) 2007-06-27 2012-05-08 Western Digital Technologies, Inc. Disk drive biasing a refresh monitor with write parameter of a write operation
US8194338B1 (en) 2010-03-31 2012-06-05 Western Digital Technologies, Inc. Parallel media defect scan in sector read
US8531793B2 (en) 2010-07-19 2013-09-10 HGST Netherlands B.V. Disk drive with variable incremented counting of writes to the data tracks for minimizing the effect of far track erasure
US8537481B1 (en) 2012-03-17 2013-09-17 HGST Netherlands B.V. Shingled magnetic recording disk drive with minimization of the effect of far track erasure on adjacent data bands
US8565053B1 (en) 2012-06-19 2013-10-22 Western Digital Technologies, Inc. Methods and devices for preventing media errors due to media scratches
US8593748B1 (en) 2012-06-04 2013-11-26 HGST Netherlands B.V. Shingled magnetic recording disk drive with compensation for the effect of far track erasure (FTE) on adjacent data bands
US8711499B1 (en) * 2011-03-10 2014-04-29 WD Media, LLC Methods for measuring media performance associated with adjacent track interference
US8793431B2 (en) 2012-03-17 2014-07-29 HGST Netherlands B.V. Shingled magnetic recording disk drive with inter-band disk cache and minimization of the effect of far track erasure on adjacent data bands
US8806117B2 (en) 2012-01-17 2014-08-12 International Business Machines Corporation Prevention of data loss due to adjacent track interference
US9165568B2 (en) 2014-03-04 2015-10-20 Kabushiki Kaisha Tosbhia Hard disk drive and data refresh method
US9330701B1 (en) 2014-12-15 2016-05-03 Seagate Technology Llc Dynamic track misregistration dependent error scans
CN105654965A (en) * 2014-12-01 2016-06-08 株式会社东芝 Magnetic disk device and operating method thereof
US9997192B1 (en) 2017-05-18 2018-06-12 Seagate Technology Llc Overlap detection for magnetic disks
US11074014B1 (en) 2019-08-22 2021-07-27 Seagate Technology Llc Managing adjacent track interference in a data storage device

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6385008B1 (en) * 1999-12-16 2002-05-07 International Business Machines Corporation Reduction of magnetic side writing in thin film magnetic heads using negative profiled pole tips
US6442705B1 (en) * 1999-04-26 2002-08-27 International Business Machines Corporation Method of and apparatus for improving data integrity in a disk drive system
US20040193798A1 (en) * 2003-03-11 2004-09-30 Hitachi Global Storage Technologies Japan, Ltd. Magnetic disk drive
US6947234B2 (en) * 2002-07-23 2005-09-20 International Business Machines Corporation Method, system, and program for performing error correction in a storage device having a magnetic storage medium

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6442705B1 (en) * 1999-04-26 2002-08-27 International Business Machines Corporation Method of and apparatus for improving data integrity in a disk drive system
US6385008B1 (en) * 1999-12-16 2002-05-07 International Business Machines Corporation Reduction of magnetic side writing in thin film magnetic heads using negative profiled pole tips
US6947234B2 (en) * 2002-07-23 2005-09-20 International Business Machines Corporation Method, system, and program for performing error correction in a storage device having a magnetic storage medium
US20040193798A1 (en) * 2003-03-11 2004-09-30 Hitachi Global Storage Technologies Japan, Ltd. Magnetic disk drive

Cited By (47)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7227708B2 (en) * 2004-11-10 2007-06-05 Hitachi Global Storage Technologies Netherlands B.V. System and method for determining long-range erasure of adjacent tracks in hard disk drive
US20060098318A1 (en) * 2004-11-10 2006-05-11 Feng Joseph S System and method for determining long-range erasure of adjacent tracks in hard disk drive
US7345837B1 (en) * 2004-12-02 2008-03-18 Maxtor Corporation Disk drive that refreshes data on portions of a disk based on a number of write operations thereto
US20060233077A1 (en) * 2005-04-12 2006-10-19 Samsung Electronics Co., Ltd Method of protecting data on recording medium and recording medium storing program for executing the method
US7477465B2 (en) * 2005-04-12 2009-01-13 Samsung Electronics Co., Ltd. Method of protecting data on recording medium and recording medium storing program for executing the method
US20060245102A1 (en) * 2005-04-27 2006-11-02 Nelson Cheng Method and apparatus for improving the error rate of track information on a magnetic storage device
US7567400B2 (en) * 2005-04-27 2009-07-28 Hitachi Global Storage Technologies Netherlands B.V. Method and apparatus for improving the error rate of track information on a magnetic storage device
US7436610B1 (en) 2005-10-20 2008-10-14 Western Digital Technologies, Inc. Disk drive employing different zone boundaries across disk surfaces
US7817370B2 (en) * 2007-03-28 2010-10-19 Lenovo (Singapore) Pte. Ltd. System and method to avoid disk lube pooling
US20080239545A1 (en) * 2007-03-28 2008-10-02 Daryl Carvis Cromer System and Method to Avoid Disk Lube Pooling
US7599139B1 (en) 2007-06-22 2009-10-06 Western Digital Technologies, Inc. Disk drive having a high performance access mode and a lower performance archive mode
US8174780B1 (en) 2007-06-27 2012-05-08 Western Digital Technologies, Inc. Disk drive biasing a refresh monitor with write parameter of a write operation
US7649704B1 (en) 2007-06-27 2010-01-19 Western Digital Technologies, Inc. Disk drive deferring refresh based on environmental conditions
US7672072B1 (en) 2007-06-27 2010-03-02 Western Digital Technologies, Inc. Disk drive modifying an update function for a refresh monitor in response to a measured duration
US7945727B2 (en) 2007-07-27 2011-05-17 Western Digital Technologies, Inc. Disk drive refreshing zones in segments to sustain target throughput of host commands
US7518819B1 (en) 2007-08-31 2009-04-14 Western Digital Technologies, Inc. Disk drive rewriting servo sectors by writing and servoing off of temporary servo data written in data sectors
US7768729B2 (en) 2008-01-31 2010-08-03 Hitachi Global Storage Technologies Netherlands B.V. Method, system, and computer program product for estimating adjacent track erasure risk by determining erase band width growth rates
US8094401B1 (en) 2008-03-17 2012-01-10 Western Digital Technologies, Inc. Writing high frequency pattern over a DC background to detect skip track erasure for a disk drive
US20090237842A1 (en) * 2008-03-20 2009-09-24 Kabushiki Kaisha Toshiba 1-1 Low track-per-inch (tpi) zone with reduced need for adjacent-track-erasure (ate) refresh
US7864476B2 (en) 2008-03-20 2011-01-04 Kabushiki Kaisha Toshiba Low track-per-inch (TPI) zone with reduced need for adjacent-track-erasure (ATE) refresh
US20090244775A1 (en) * 2008-03-31 2009-10-01 Kabushiki Kaisha Toshiba 1-1 Adjacent-track-erasure (ate) refresh with increased track resolution for often-written areas
US8004785B1 (en) 2008-05-09 2011-08-23 Western Digital Technologies, Inc. Disk drive write verifying unformatted data sectors
US7925828B2 (en) * 2008-07-17 2011-04-12 Kabushiki Kaisha Toshiba Magnetic disk drive refreshing data written to disk and data refreshment method applied to magnetic disk drive
US20100014183A1 (en) * 2008-07-17 2010-01-21 Kabushiki Kaisha Toshiba Magnetic disk drive refreshing data written to disk and data refreshment method applied to magnetic disk drive
US7929234B1 (en) 2009-03-27 2011-04-19 Western Digital Technologies, Inc. Disk drive prioritizing in-the-field defect scanning based on number of write operations in each of a plurality of defect zones
US7974029B2 (en) 2009-07-31 2011-07-05 Western Digital Technologies, Inc. Disk drive biasing refresh zone counters based on write commands
US20110026159A1 (en) * 2009-07-31 2011-02-03 Western Digital Technologies, Inc. Disk drive biasing refresh zone counters based on write commands
US20110075290A1 (en) * 2009-09-25 2011-03-31 Lenovo (Singapore) Pte. Ltd. Systems and methods for adjacent track interference (ati) risk management
US8331053B2 (en) * 2009-09-25 2012-12-11 Lenovo (Singapore) Pte. Ltd. Systems and methods for adjacent track interference (ATI) risk management
US8094396B1 (en) 2010-02-11 2012-01-10 Western Digital Technologies, Inc. Media defect scan
US8194338B1 (en) 2010-03-31 2012-06-05 Western Digital Technologies, Inc. Parallel media defect scan in sector read
US8014097B1 (en) 2010-05-07 2011-09-06 Hitachi Global Storage Technologies Netherlands B.V. Disk drive with adaptive counting of writes to the data tracks for minimizing the effect of adjacent track encroachment
US8023215B1 (en) 2010-05-25 2011-09-20 Seagate Technology Llc Data recovery scan based on head performance
US8531793B2 (en) 2010-07-19 2013-09-10 HGST Netherlands B.V. Disk drive with variable incremented counting of writes to the data tracks for minimizing the effect of far track erasure
US9025264B1 (en) 2011-03-10 2015-05-05 WD Media, LLC Methods for measuring media performance associated with adjacent track interference
US8711499B1 (en) * 2011-03-10 2014-04-29 WD Media, LLC Methods for measuring media performance associated with adjacent track interference
US8806117B2 (en) 2012-01-17 2014-08-12 International Business Machines Corporation Prevention of data loss due to adjacent track interference
US8793431B2 (en) 2012-03-17 2014-07-29 HGST Netherlands B.V. Shingled magnetic recording disk drive with inter-band disk cache and minimization of the effect of far track erasure on adjacent data bands
US8537481B1 (en) 2012-03-17 2013-09-17 HGST Netherlands B.V. Shingled magnetic recording disk drive with minimization of the effect of far track erasure on adjacent data bands
US8593748B1 (en) 2012-06-04 2013-11-26 HGST Netherlands B.V. Shingled magnetic recording disk drive with compensation for the effect of far track erasure (FTE) on adjacent data bands
US8565053B1 (en) 2012-06-19 2013-10-22 Western Digital Technologies, Inc. Methods and devices for preventing media errors due to media scratches
US9165568B2 (en) 2014-03-04 2015-10-20 Kabushiki Kaisha Tosbhia Hard disk drive and data refresh method
CN105654965A (en) * 2014-12-01 2016-06-08 株式会社东芝 Magnetic disk device and operating method thereof
US9330701B1 (en) 2014-12-15 2016-05-03 Seagate Technology Llc Dynamic track misregistration dependent error scans
US9997192B1 (en) 2017-05-18 2018-06-12 Seagate Technology Llc Overlap detection for magnetic disks
US10319405B2 (en) 2017-05-18 2019-06-11 Seagate Technologies Llc Overlap detection for magnetic disks
US11074014B1 (en) 2019-08-22 2021-07-27 Seagate Technology Llc Managing adjacent track interference in a data storage device

Similar Documents

Publication Publication Date Title
US20060066971A1 (en) System and method for ameliorating the effects of adjacent track erasure in magnetic data storage device
US6947234B2 (en) Method, system, and program for performing error correction in a storage device having a magnetic storage medium
TWI254917B (en) Magnetic disk device
US7738208B2 (en) Data recovery through eliminating adjacent track interference
KR100630745B1 (en) Method to preserve data on recording medium and recording medium having a program therefore
US7274639B1 (en) Disk drive performing multi-level prioritization of entries in a suspect sector list to identify and relocate defective data sectors
US7681071B2 (en) Storage apparatus, control method therefor and program
JP5143429B2 (en) Hybrid hard disk drive control method, recording medium, and hybrid hard disk drive
US7333279B2 (en) System and method for drive-side guarantee of quality of service and for extending the lifetime of storage devices
US6898033B2 (en) Anticipating media decay in a disc drive
JPWO2009040929A1 (en) Storage device, control method, and control device
US7757154B2 (en) Magnetic disk control apparatus, magnetic disk apparatus, and method of correcting read error
US8028137B2 (en) System and method of selective data mirroring in a data storage device
JP2007310974A (en) Storage device and controller
US10559322B2 (en) Diagnostic tape cartridge patterned with predetermined head-media spacings for testing a tape head of a tape drive
US7920352B2 (en) Magnetic disk apparatus and data storage method
US20070025005A1 (en) Method of protection of information of depopulated magnetic disk apparatus
US7809978B2 (en) Storage device and control device
US20050154950A1 (en) Method for saving self-test output to both flash and media
JP2006286128A (en) Magnetic disk device
JP2010146674A (en) Magnetic disk drive, controller and control method
US20090249109A1 (en) Storage apparatus and method for storing internal information
US20050154951A1 (en) Saving self-test output to both flash and media
US20220027056A1 (en) Region-specific directed offline scan for hard disk drive
US6631043B1 (en) Elimination of three pass write

Legal Events

Date Code Title Description
AS Assignment

Owner name: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS B.

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:ALEX, MICHAEL;ZAITSU, HIDEKI;REEL/FRAME:015869/0121;SIGNING DATES FROM 20040929 TO 20040930

STCB Information on status: application discontinuation

Free format text: ABANDONED -- AFTER EXAMINER'S ANSWER OR BOARD OF APPEALS DECISION